It is well known that temptations arise when service personnel handle cash collected by a currency validator. It is also known that vandals target currency validators. Thus, it is expected that the cash box connected to such devices will be abused.
When a cash box which contains cash that is less than that amount for which services or change were rendered is delivered to a central office, it is uncertain whether or not the validator malfunctioned, or if the serviceman is dishonest. Therefore, it is desirable to provide a removable, lockable cash box for currency validators in which the stored bills cannot be accessed by service personnel.
Thus, lockable, removable cash boxes for use with currency validators have been developed. See, for example, U.S. Pat. Nos. 4,949,901, 4,977,583 and 4,997,128. In these patents, a cash box connected to a currency validator receives accepted bills and locks prior to its removal from the validator. Service personnel remove the cash box at predetermined intervals or when it is full, and replace it with another empty one. The full cash box is then taken to a central office where it is opened with a separate key.
The cash box described in U.S. Pat. No. 4,997,128 employs a continuous sleeve having a window. When connected to a bill acceptor, the sleeve is positioned to receive bills through the window. Before removal, the sleeve is rotated around rollers by a motor or by the release of a torsion spring, to close the window. The sleeve does not appear to be durable, and therefore forced entry into the cash box to steal bills might be attempted. Further, the spring loaded embodiment may be susceptible to being opened by shocks, such as dropping the cash box onto the pavement. A serviceman may then be tempted to steal some bills and relock the cash box, known as skimming bills, before delivery to the central office.
The cash box described in U.S. Pat. No. 4,949,901 employs a semi-cylindrical inner housing which rotates upon removal into a position to prevent access to the stored bills. The rotation may cause jamming of bills, thus preventing removal of the cash box from the validator. Further, machines which employ cash boxes often have limited space, and this design is not compact. Therefore, the size of the bill storage compartment is limited by the size of the housings required to permit rotation of a large amount of bills.
Other lockable prior art cash boxes have used electronic solenoids to move various pusher plates, electronic counters to keep track of the amount of bills stored, and other circuitry to attempt to deal with the potential theft and fraud problems. Yet other approaches have used fragile spring locking mechanisms. These designs were expensive to manufacture and maintain, and could be relatively easily defeated by cutting power to the system, by rough treatment of the cassette, or by some other tampering.